Gas'-meter

(-me'tr.) Before the gas is consumed it is usually pa ed through an instrument called a meter, in order to ascertain the number of cubic feet which are used in a given time, or in a particular place. The instrument consists of ak ind of revolving drum, having compartments which measure the gas, and deliver it, as they pa round in succe ion; water,which, before the next revolution, is replaced by gas, taking its place. It is filled with that fluid up to a certain height through an orifice in the side of the ve el, in which a plug is fitted. The gas enters by a pipe at one side, escapes from an orifice into a pipe at the other, and is thence conveyed to the burners. By means ofa train of wheelwork in connection with the axis of the drum, an index is turned, which points out on the index-plate how many cubic feet have pa ed through. [s. 397]